#include <iostream>
using namespace std;

int main(void){
//input
	int num; cin >> num;
//calc
	int z=0;
	for(int i=1;i<=num;i++){
		if(i % 3 == 0 && i % 5 == 0){
			z += 4;
		}else if(i % 3 == 0 || i % 5 == 0){
			z += 2;
		}
	}
//output
	cout << z;
}